Device (with custom DTH) not connecting to Smartthings hub (3rd gen)

I setup a new Samsung account and added the new Smartthings hub (3rd gen) to the new Smartthings app. I went to and added my custom DTH to support my ZigBee device. However, when I try to add a thing in the app, it isn’t added. How can I fix this?


  • the green LED doesn’t blink on the 3rd gen hub when I try to add device
  • I made sure I added my custom DTH to the correct location
  • this DTH is [ vid:“generic-switch” ]
  • it worked on the 2nd gen hub just fine

It appears that I have to “add device manually” by clicking any device from the drop down selection. Then the green LED blinks, indicating scanning mode. Is it possible to just simply click “add device” only?

  1. do not use the graph.api URL. Instead use
  2. for custom code, it is recommended that you install and use the SmartThings Classic app instead of the Samsung Connect app at this point.
  3. which dth are you trying to modify to work in the new app? Or which zigbee device?